Sphygmomanometer



March 7, 1933, w. l. HUBER ET AL S-PHYGMOMANOMETER Filed Deo. l2, 1929 vll Patented lll/leur.y i 7, 1933 AUNITED STATES PATENT oFFlcEl WARD VI. HUBER AND LOWELL B. CLOSE, OF CLEVELAND, OHIO, ASSIGNORS` 'TO W. I. HUBER, INC., F CLEVELAND, OHIO, A'CORPORATON OF OHIO sPHYeMoMANor/IETER Application ined December 12, V1929. serial No. 413,567.

Our invention relates to an improvement in s h momanometers land our ur ose in general is to provide a small mercury instrument adapted to apply pressure in a small 5 spot like area over an arteryuntil itis so compressed that the flow of blood is stopped yentirely or persists only during apart ofthel cycle, the pressure of the blood in the artery being indicated in terms of the height in millimeters of a mercury: column. The instrument is of small dimensions and includes a graduated pressure indicating tube having a compressible member at its bottom whereby an artery may be compressed and a body of mercury simultaneously displaced and quantitatively trammitted instantaneously to the tube. The instrument is also particularl7 constructed to permit oscillation of the mercury without building up an internal air presdiastolic pressure, while sealing the merl cury at all times against exposure to the atmosphere. For such purposes we use a collapsible air bag of greater capacity than the receiving bore for the mercury column, `which bag is extremely sensitive tothe movement of the mercury withinthe column and offers no resistance to its rise or fall to any height or elevation therein. The'instrument yis also particularly designed to facilitate its `production and assembly, to give accessibility to its parts, and to permit convenient inspection, tests, replacements and repairs, all as hereinafter more fully explained.

instrument open. Fig. 6 is a sectional view Figs. 7

longitudinally of the instrument. and 8 are sectional and perspective views, respectively, of the closure cap and collapsible bag separator, and Fig. 9 is a side elevation of the same parts united together. Fig. 10 is a sectional view of the air displacementk cyla inder used at the top of the instrument, and

sure, and to promote readings of systolic or fout restraint. thin and flexible that no inherent tension of In the accompanying drawing, Fig. 1 is a vvide an air and liquid seal, and the lower por- Figs. 11, 12 andi?) are perspective views of the upper sealing band, the glass column, and

ing 6 in its bottom. An elongated rubber bag 7 having a thin distensible and collapsible 5 wall is suspendedA within chamber 5 from a Iianged cap 8 having screw connection with the upper end of cylinder 4. The bag is secured at its upper end, which is open, to the Cap vby a stiif ring 9 which is ofsuiiicient 70 diameter to compress-the rubber edge of the bag with binding and sealing effect against the screw flange of the cap. However, an inclined passage 10 in the top of cap 8 provides constant open communication'between 5 the interior of bag- 7 and the atmosphere,

thereby permitting kthe bag to collapse with- The wall of the bag is also so any consequence hinders the buckling of the bag inwardly when air is forced through opening 6 'into air chamber 5. This occurs when acolumn of mercury 11 is forced upwardly in a bore 12 ofrelatively small diameter in a glass tube 14 attached to neck 3 of cylinder 4. lA rubber bandl encircles the upper end of the glass tube within neck 3 to cushiony and protect the glass and to protion ofthe glass tube is also securedand sealed 0 inI like manner by a larger rubber band or gasket 16 where it is pressed into Aan annular channelV at the bottom of a cylindrical enlargement 17 on barrel 2, seeFig. 6. The lower end of the glass tube is also enlarged land provided with a larger bore or well 18 within which a short column of mercury stands at a predetermined level when the instrument is not in use. The main body of mercury M is coniined within a rubber boot 0r 00 pressure applicator 19 having relatively thick side walls 2O and a thin flexible bottom 2i. rlhe upper end of applicator 19 is open and circular and the wall reduced in thickness to permit it to be sleeved over the cylindrical enlargement l? on barrel 2 where it may be screw-engaged and compressed tightly against enlargement l? by a rotatable collar 22. The reduction in thickness of the upper wall of the applicator or vboot provides an annular shoulder 23 internally which is engaged by the bottom edge of the barrel and takes the thrust of the instrument when it is pressed downwardly to constrict an artery.

A. direct pressure is applied through the l rubberboot and there is very little surrender. or yield in the thick walls of the boot, especiallyr the two side walls which extend on straight parallel lines the full length of the boot to bottom2l see Fig. 5. r.ihe boot is also formed in part with flaring walls to provide a bottom 2l approximately twice as long as it is wide, and this elongated bottom is thin and elastic although slack and not under ten sion when not distended by the weight of the mercury. rllius, when the instrument is suspended apart from a place of rest, bottom 2l bulges downwardly and is stretched in some degree by the weight of the mercury, but when the instrument is permitted to settle upon a supporting surface the bottom will flatten out until it is slack and free to flex within limits without tension. The column of mercury may thus be placed at rest in a localized area over an artery and the walls of the artery compressed at two places where the thick walls of the boot engage the surface, then the `pressure of the instrument may be directly utilized in overcoming the pressure of the blood in the artery, allowance being made in Calibrating the instrument for the slight resistance ofl'ered by the small area involving the tissues of the arm and the walls of the artery, and any variation in the capillary action of the mercury.

rlhe fluctuations in pressure are transmitted instantaneously to the mercury and the oscillations may be watched through the glass tube to determine the points of systolic or diastolic pressure, readings being obtained by a scale 24e in millimeters of mercury. Scale 24 consistsof a piece of celluloid or other transparent material partly circular to conform to and lit within the circular wallof barrel 2, and partly flater substantially flat to span the open side of barrel 2 and to bring the graduated markings close to the glass tube. rlhe lower end of this celluloid piec-e 24 is circular and fits snugly within the enlarged part 17 of the barrel where itis seated upon the rubber band or gasket 16. A. rotatable sleeve 25 encases barrel 2, one side being open for part of its length to expose the transparent scale when given one half yof a turn relatively to the barrel. A pin 26 in one side of barrel 2 co-acts with the end walls of a semi-circular slot 27 in sleeve 25 to limit the rotatable movements of the sleeve, which rotative movement may be easily eected by gripping a knurled enlargement 28 at the upper end of the sleeve where it overlaps the sides and abuts against the bottom of cylinder 4l. V] hen this cylinder or head piece is unscrewed from barrel 2, the sleeve 25 and other parts may be readily separated, but when all the parts are firmly connected together the mercury is sealed at all points and can not escape inasmuch as the boot closes the bottom and the air bag 7 seals the top of the tube. 0n the other hand the air coni'ined within the glass tube is easily transferred to air chamber 5 within cylinder head 4 without compression and no resistance is offered to the upward movement of the mercury, vinasmuch as bag 7 has a greater air capacity than the bore in the mercury tube and because the circular walls of the bag are thin and of suflicient area to buckle-in very freely. ln addition continuous sealing by air bag 7 rprevents loss of mercury, exposure of the mercury to the atmosphere, darkening of the instrument by oxidation, and intake of dirt.

lWhat we claim is:

l. A sphygmomanometer, comprising a transparent tube having a mercury container connected therewith, the bottom of said container being yieldable to elfect displacement and uplift of the mercury and the border edge of said container being yieldably resistant to thrust to effect compression of an artery in a circumscribed area, and a fleX- ible air bag suspended above the top of the tube and sealing the same against the open atmosphere.

2. A sphygmomanometer, comprising a tubular column having an enlarged bore in its base portion, a yieldable artery constriction device containing a liquid and provided with a sensitive vibratory diaphragm adapt' ed to displace the liquid and transmit the pulsations of an artery to the liquid forced into said column, a detachable hollow member open to the upper end of said tube and a thin flexible bag Aopen internally to the atmosphere and suspended therein for seal ing the tube against the open atmosphere.

3. A sphygmomanometer, comprising a transparent tube with measuring indicia lengthwise of said tube, a yieldable boot at' the bottom of said tube having a portion thereof adapted to yieldingly apply a constricting pressure to an artery and another portion to vibrate with the pulsations of the artery while it is being constricted, said boot containing a liquid adapted to be displaced by the movements of both portions thereof, a cylinder having an air chamber open to the upper end of said tube, and a detachable cap for said cylinder having a CII collapsible bag suspended therefrom and displacing air within said chamber, the interior of said bag being open to the atmosphere.

4. A .sphygmomanometen comprising a transparent vertical tube, a chamber at its bottom having a slightly yieldable circumferential side wall and a more readily yieldingbottom, and a collapsible device for sealing the upper part of said tube, said circumferential side wall being adapted to constrict a blood vessel at two distinct places,

when said chamber is pressed downwardly upon such blood vessel.

5. A sphyginomanometer, comprising a transparent tube, a mercury filled yielding boot therefor having a thin yielding bottom and a circumferential integral side wall of greater wall thickness `and less yield than said yielding bottom, a hollow head for said tube anda flexible air displacement bag within said head communicating with the atmosphere and sealing the upper part of the tube from the atmosphere.

6. A sphygmomanometer, comprising a vertical transparent tube, a compressible member attached to the bottom of said tube, said member including an integral circumferential side wall of less yielding properties than the freely yielding bottom of said member, to permit constriction of an artery at two distinct places when said sphygmomanometer is `forced downwardly upon said artery, said tube containing a liquid element exposed to and constantly subject` to the movements of said compressible member, an air chamber at the top of said tube and a collapsible air bag within said chamber and for sealing same against the open atmosphere,

head, 'sealing gaskets between said tubel and head and said tube and barrel, a cap member vtor said head having an air opening therein,

tures. f

WARD I. HUBER. LOWELL B. CLOSE.

the air capacity of said bag being at least n y equal to the air space within the tube.

7. A sphygmomanometer, comprising ay slotted barrel, a slotted Vsleeve rotatably mounted upon said barrel, a transparent tube i within said barrel, a graduated scale within said barrel opposite said tube, a boot filled with mercury connected with said barrel and communicating with said tube and having a thin bottom and provided with side walls adapted to compress a blood vessel and simultaneously force a portion of the mercury in said boot upwardly into said tube, a hollow head detachably connected to the upper end of said barrel and serving as a retaining member for said sleeve, and collapsible sealing means for said tube connected to said head. Y

8. A sphygmomanometer, comprising ka transparent tube containin g mercury, a transparent scale sleeved over said tube, a yieldable boot at the bottom of said tube adapted to compress an artery and transmit a pulsating movement of the artery upwardly to the mercury in the column, a hollow head for said tube, a barrel connecting said boot and 

